Fix README
Revert "Make module"

This reverts commit 8bb8b9a72f6079ecf1cab1f028424c0ff936808b.
Revert "Move source to package directory"

This reverts commit 2075a36709f28ec38aa0ca3c4ca3763b0bafa96c.
Move sparse_list into the root package for v0.2
Add Travis CI